Field of Invention
Various embodiments of the present disclosure relate to a thin optical lens capable of actively zooming in and/or out and an apparatus using the same, and more particularly, to a thin optical lens capable of adjusting the position of a lens structure using deformation of a transparent thin polymer film having high elasticity, without interlocking with a separate external drive unit for changing the position of the lens, and to an optical apparatus using the same.
Description of Related Art
Recently, for cameras, potable terminals, TVs, projectors, medical devices, etc. that are based on the digital technology, a reduction in thickness and weight of optical systems pertaining to high-resolution imaging is required as the display technology is developed. For this, the importance of a reduction in size of an optical zoom apparatus is being further emphasized.
To embody an optical zoom function in a camera module, a technique using a separate actuator to vary the position of a lens may be used. A step motor may be used as a method for embodying the optical zoom function. In this case, a movable unit may be linearly moved by rotating a lead screw using a drive unit which generates rotational motion. However, in such a method, complex mechanism is required. Furthermore, friction is generated in a gear unit, whereby noise may be caused.
To provide an automatic zoom function, a method of using a voice coil motor (VCM) or a piezoelectric ceramic actuator may be used. The method of using the VCM is a method in which electromagnetic force by a magnet and current flowing through a coil is used to generate drive force for embodying the automatic zoom function. However, electromagnetic waves are generated, and the precision is limited. The method of using the piezoelectric ceramic actuator is a method in which friction between a stator and a rotor is used to generate drive force for embodying the automatic zoom function. However, there are disadvantages in that the lifetime is reduced by abrasion, and the production cost is comparatively high.
Most of the existing techniques such as the above-mentioned examples have complex structures resulting in an increase in the production cost. In addition, it is difficult to reduce the size, so that a reduction in thickness and weight of an optical zoom apparatus is limited.